Nepenthes hamiguitanensis

Nepenthes hamiguitanensis

Synonymy

Nepenthes hamiguitanensis Gronem., Wistuba, V.B.Heinrich, S.McPherson, Mey & V.B.Amoroso in McPherson, Carniv. Pl. Hab. 2: 1296 (-1305; figs. 759-766). 2010 sec. Cheek & Jebb 2013
    • Type (designated by Gronemeyer, T., Wistuba, A., Heinrich, V.B., McPherson, S. R., Mey, F.S. & Amoroso, V.B. 20101): Philippines, Mindanao Island, Davao Oriental Province, Mount Hamiguitan, trail from San Isidro in mountain forest margins on the summit ridge, 1310 m, March 13, 2007. V. Amoroso and R. Aspiras CMUH00006494, Central Mindanao Univierstiy Herbarium, Musuan, Bukidnon, Philippines (CMUH).
  • 1. Gronemeyer, T., Wistuba, A., Heinrich, V.B., McPherson, S. R., Mey, F.S. & Amoroso, V.B. 2010: Nepenthes hamiguitanensis (Nepenthaceae), a new pitcher plant species from Mindanao Island, pp. 1296-1305. – In: McPherson, S. R., Carnivorous plants and their habitats 2

Description

Terrestrial climber, up to 4 m tall. Stem cylindrical, 8-10 mm diameter, internodes 4-7 cm.
Leaves of the climbing stem petiolate, lamina elliptic to oblong, 20-25 cm long and 6-9 cm wide, apex obtuse, base gradually attenuate to the canaliculate petiole. Petiole sessile, up to 9 cm long. Longitudinal nerves 3 on each side of the midrib; pennate nerves numerous, running obliquely to the margin. Tendril about as long as the leaf, mostly with curl.
Upper pitchers up to 20 cm tall and up to 9 cm wide, infundibular in the lower half, with a distinct hip around the middle, cylindrical to slightly infundibular towards the pitcher opening. Wings reduced to ribs throughout. Mouth oblique, 6-8 cm wide, elevated towards the lid, elongated into a neck. Peristome cylindric, sometimes slightly flattened, 1 cm wide, ribs 0.3 mm apart, teeth of the inner margin 1 mm long. Inner surface glandular in the lower half. Lid cordate, 5 cm wide, glands evenly distributed over the whole lower surface, distinct appendage near the peristome attachment. Spur bifurcated, 3-4 mm long.
Lower pitchers were observed only on seedling-plants at the type locality and are not included in the holotype.
Male inflorescence ca. 70 cm long, 3.5 cm wide, partial pedicels branched and 2-flowered, bracts absent. (Inflorescence measurements are based on data recorded at the type locality, 23.7.2008, owing to the absence of such material in CMU Herbarium.)
Indumentum present throughout, especially prominent at the leaf margins; consists of coarse, short light brown to white hairs.
Colour variable, pitchers usually creamy-white but also red-speckled on creamy ground. Peristome either in the same colour as the pitcher, dark-red or red-striped.A

Conservation

Assessed as VU according to the World Conservation Union Red List cirteria. A

Distribution (General)

Philippines, Mindanao Island, Mount Hamiguitan.A

Etymology

The species epithet was chosen to denote that this remarcable species is endemic to Mount Hamiguitan.A

Habitat

Nepenthes hamiguitanensis grows exclusively in primary, intact mountain forest and forest margins between 1200 m and 1600 a.s.l. on the summit ridge. It is absent from the distinct bonsai field that stretches across the plateau below the summit ridge. The plants grow predominantly in partially shaded conditions and receive heavy rain regularly. Although Mt. Hamiguitan is an ultramafic mountain, N. hamiguitanensis does not necessarily grow on ultramafic soil as the forest underlayer is rich in humus.A

Bibliography

A. Gronemeyer, T., Wistuba, A., Heinrich, V.B., McPherson, S. R., Mey, F.S. & Amoroso, V.B. 2010: Nepenthes hamiguitanensis (Nepenthaceae), a new pitcher plant species from Mindanao Island, pp. 1296-1305. – In: McPherson, S. R., Carnivorous plants and their habitats 2

Specimens

CountryDateCollector + collecting numberHerbariaTypeScanDerivatives
Philippines
Citation: Philippines.

Specimen summary: Philippines, Mindanao Island, Davao Oriental Province, Mount Hamiguitan, trail from San Isidro in mountain forest margins on the summit ridge, 1310 m, March 13, 2007. V. Amoroso and R. Aspiras CMUH00006494, Central Mindanao Univierstiy Herbarium, Musuan, Bukidnon, Philippines (CMUH).
Type for: Nepenthes hamiguitanensis Gronem., Wistuba, V.B.Heinrich, S.McPherson, Mey & V.B.Amoroso